1. Field of the Invention
The present invention relates to a package for micro-electro-mechanical acoustic transducer with surface mountable electrodes. More particularly, the present invention relates to a package with selectively double side mountable electrodes for being mounted to a user's circuit board.
2. Description of Related Art
micro-electro-mechanical acoustic transducers are becoming more and more popular because of its low profile, excellent characteristics with multiple functions and easy to be integrated with integrated circuits. Silicon condenser microphone is one of the types of the micro-electro-mechanical acoustic transducer microphones. This kind of microphone is widely used because it has stable and consentaneous characteristics and is easy for being surface mounted on a circuit board. The transducer unit of this kind of microphone is usually manufactured from silicon through micro-electro-mechanical technology. It is a common knowledge that an integrated microphone must include a package in order to protect the inner transducer unit and some other electronic components.
The traditional silicon condenser microphone includes a microphone transducer unit, a readout circuit unit, a filter capacitance and an out shell accommodating the microphone transducer unit, the readout circuit unit for electrical signal output and the filter capacitance for EMI suppression. The out shell defines an acoustic aperture for allowing sound waves to reach the microphone transducer unit. A plurality of electrodes is provided for outputting signals. Such electrodes are adapted for being surface mounted on a user's circuit board as a result that the silicon condenser microphone can be electrically connected with outside components.
However, with fast development of such silicon condenser microphone, various surface mountable modes of the electrodes are required. For example, in some conditions, the silicon condenser microphone is required to be surface mounted from one side in which the acoustic aperture is defined. While in some other conditions, the silicon condenser microphone is required to be surface mounted from another side opposite to the acoustic aperture. The traditional silicon condenser microphone only has certain mounting surfaces and is suitable for a special condition while it can't meet both of the above-mentioned mounting conditions.
Hence, it is desired to have an improved package with selectively double side mountable electrodes solving the problems above.